From Ohio History Central

In 1871, James Ritty became a saloon owner in Dayton, Ohio. Unfortunately for Ritty, some of his employees stole money from the business. In 1878, while on a ship bound for Europe, Ritty saw a machine that counted the number of times that the ship's propeller completed a revolution. Using the same sort of technology, Ritty became convinced that he could invent a machine that could keep track of his sales. Ritty returned to the United States, and with the assistance of his brother, a mechanic, he invented the first cash register. He patented his invention on November 4, 1879, and called it "Ritty's Incorruptible Cashier." Ritty's machine did not have a cash drawer. Instead, it simply recorded the number of sales and also the amount of each one. This machine allowed Ritty to keep accurate track of the number of sales and the amount of each sale that was made.

Upon patenting his invention, Ritty established a company to manufacture the cash registers in Dayton. Unfortunately, Ritty's invention did not draw much enthusiasm from other business owners, and Ritty's new company quickly closed. Ritty eventually sold his patent to a group of Ohio investors. Among them was John H. Patterson, who eventually turned Ritty's invention into a fortune. In 1884, Patterson founded the National Cash Register Company.